Answer:
45
Step-by-step explanation:
2 digit number starts from 10 ends at 99
between 10 and 19 there is only one number whose tens digit is more than ones digit.
that is 10
between 20 and 29 there are two numbers
20 and 21
like the same
between 30 and 39 there are 3 numbers
10–19. 1
20–29. 2
30–39. 3
40–49. 4
50–59. 5
60–69. 6
70–79. 7
80–89. 8
99–99. 9
sum of first n natural numbers is n(n+1)/2
9(9+1)/2=45
One company wants $10 per 3.5 hours, so they want 10 / 3.5 ≈ 2,86 dollars per hour (after rounding to the closest hundreths).
Second company wants $1.25 per half an hour, so they want 2 * 1,25 = 2,50 dollars per hour.
The unit rate is 2,86:2,50
Answer:
1 2/9 minutes
Step-by-step explanation:
55 mph
55 / 60 = 11/12
11/12 of a mile = 1 minute
45 mph
45 / 60 = 3/4
3/4 of a mile = 1 minute
11/12 divided by 3/4
11/12 * 4/3
We can cross-cancel
11/3 * 1/3 = 11/9 = 1 2/9
It takes 1 2/9 minutes for the hummingbird to cross the lake
Hope this helps!
(Please let me know if I did something wrong!)
Ok so let T=time from when Tim starts
Distance Tim travels= T*90
Distance Dora travels=T*75 + 75 (<as already started)
for him to have caught up His distance must equal hers so:
90T=75T + 75 (now minus 75T)
15T=75 (now divide by 15)
T=5 :)
So five hourse, hope this helped :)
Answer:
A
Step-by-step explanation:
edge 2020
